124 PROCEEDINGS OF THE AMERICAN ACADEMY 



external ramus a little longer than the internal, laterally flattened, 

 ending in a slender, sharp point. 



Male, form II. Rostrum with small lateral teeth ; hand smaller, 

 with smaller tubercles ; hooks on third legs smaller ; third pair of 

 abdominal appendages stoutei', cleft for only a short distance from the 

 tip, tips blunt, no articulation at the base in the one specimen exam- 

 ined. 



Female. Rostrum as in the second form of the male. Hand shorter 

 and broader, annul us ventralis with a very deeply excavated fossa. 



Measurements of male, form I. : — Length, 73 mm. Length of ros- 

 trum, 9 mm. Breadth of rostrum at base, 5 mm. Length of areola, 

 11 mm. From tip of rostrum to cervical groove, 25 ram. Length of 

 chela, 35 mm. Breadth of chela, 14 mm. Length of inner finger, 

 24 mm. Length of internal margin of hand, 11 mm. 



Five specimens, one male, form I., one male, form II., and three 

 females, were collected by Prof. O. P. Hay in Eastern Mississippi. 

 Two of them are labelled " Macon, Miss." 



Differs from G. immunis in its linear areola, flatter rostrum, differ- 

 ently shaped chela, and male appendages, the rami of which are longer 

 and less strongly recurved. C. Palmeri differs from it in its quad- 

 rangular rostrum, which has a longer acumen and more prominent 

 lateral spines, narrower and long-spined antennal scale, longer areola ; 

 the rami of the male appendages (form II,) are a little longer and 

 more widely separated. C Alabamensis differs by its wide areola, 

 toothed and carinated rostrum, etc. ; G. compressus, by its laterally 

 compressed carapace, wide areola, narrow carinated rostrum, etc. 



b. Rostrum with lateral teeth. 



14. C. Palmeri, sp. no v. 



Male, form II. Rostrum broad, sub-excavated, margins nearly 

 pai'allel from base to lateral spines, which are small and sharp ; acu- 

 men long. Post-orbital ridge with sharp anterior spine. Carapace 

 smooth and punctate above, granulate on sides, lateral spine of moder- 

 ate size, anterior lateral border notched just below the sub-orbital 

 angle, which is not prominent. Areola linear for a short distance 

 antei'ior to the centre, with a small anterior and a larger posterior 

 triangular field. The length of the areola is one half the distance from 

 cervical groove to tip of rostrum. Abdomen as long as the cephalo- 

 thorax. Proximal segment of telson bispinose on each side. Anten- 

 nte nearly as long as the body. Lamina a trifle longer than rostrum, 



